This application relates generally to a die and, more particularly, to a die for bending flat metal stock.
Fixed V-shaped female dies and punches are used commonly to bend flat metal stock and particularly sheet metal into precise angles. A primary disadvantage of V-shaped female dies and punches is their inherent tendency to produce distinctly perceptible scores on the metal stock adjacent to the bend along the line at which the edges of the female die engage the sheet metal stock when the punch is rammed into the stock to move it into the die. Such scores are highly objectionable to manufacturers having rigid quality specifications.
An improved flat metal stock bending die is disclosed in U.S. Pat. No. 2,882,952. That patent discloses a die employing a pair of parallel elongated die bars having a semi-circular cross sectional configuration and mounted for pivotal movement along their longitudinal axes. Although offering some improvement over V-shaped die and punch assemblies, the die disclosed in U.S. Pat. No. 2,882,952 fails to completely eliminate the problem of material scoring because of a certain degree of relative movement that occurs between the die bars and the flat metal stock during a bending operation.
The object of this invention, therefore, is to provide an improved die for use with a punch for bending flat metal stock.